Geographical position extension in messaging for a terminal node

ABSTRACT

The present invention provides methods and apparatus for supporting geographical-based services in a communications system. In an embodiment of the invention, a terminal node (e.g., a wireless terminal) inserts geographical information into a header portion of an IPv6 datagram. The serving network utilizes the geographical information to support a geographical-based service. In another embodiment, a terminal node, which is located in a geographical area, receives service configuration information regarding service regions from a serving network and determines what services are supported in the geographical area. In an embodiment, header formats for the inserted geographical information in a propagated signal between a terminal node and a serving network are provided.

FIELD OF THE INVENTION

The present invention relates to supporting geographical-based servicesin a communications system for a terminal. In particular, the inventionrelates to apparatus and methods in which geographical information isinserted in messaging.

BACKGROUND OF THE INVENTION

Communication terminals are becoming increasingly portable while thesupported services are becoming increasingly complex and diverse.Moreover, users require services that are based upon the location of theuser. 911 emergency services is a ubiquitous example. Moreover, thenumber of geographical-based services is becoming more prevalent fornon-emergency purposes. With mobile users carrying video-capablewireless terminals, for example, these users may wish to obtaininformation about restaurants in the local vicinity. By including thegeographical position of the user's terminal with specificcharacteristics of the restaurant (e.g., type of cuisine and pricerange), a content server may provide a menu of a specific restaurant onthe terminal's video display. The number of potential geographical-basedservices is staggering and is only limited by an entrepreneur'simagination.

With the prior art, geographical-based services are typically limited.For example, with Internet Protocol (IP) capable terminals, the locationof a user is often predicated on the associated IP address. However,there may be a low correlation between the location and the value of theIP address, particularly if the IP address is static. Thus, deriving thelocation from the IP address may be very inaccurate. Also, with somewireless standards, such as Global System for Mobile Communications(GSM) and Universal Mobile Telecommunications System (UMTS), if awireless terminal does have locating capabilities, position informationmay be included in signaling messages that are distinct from messagesthat contain associated data payloads.

Thus, there is a real need in the industry to provide methods andapparatuses for supporting geographical-based services that integrategeographical information with existing messaging and that is flexible.For example, geographical-based services should operate transparentlyeven though the geographical-based services may be implemented ondifferent platforms and architectures, including hybrid systems.Moreover, it is desirable that a communications system enables a user toselect different options for geographical-based services if thecommunications system supports these options.

BRIEF SUMMARY OF THE INVENTION

An aspect of the present invention provides methods and apparatus forincluding geographical information in existing messaging. Thus, anexisting message type that supports a data payload may also contain thegeographical information in the same datagram. An embodiment of theinvention supports a header extension that is compatible with IPv6specifications, in which a geographical position, velocity information,and uncertainty information about the geographical position and thevelocity information of a terminal node are contained in a destinationoptions header or a hop-by-hop header. The terminal node connects withan attachment point, which passes datagrams to a content server througha router. The content server may use the geographical information todetermine the geographical-based services that are available to theterminal node.

With another aspect of the invention, a destination position and aspecified radius may be included in header information of a datagramfrom a terminal node. The destination position and radius are used forspecifying an area, e.g., defined as a polygon having three or morecomer points. The area, which may be expressed as a polygon, can beapproximated as a circle. The serving network uses the geographicalinformation to broadcast a geographical-based service to anotherterminal node through a Digital Video Broadcasting (DVB-T) network in anarea defined by the geographical information.

With another aspect of the invention, a server parses geographicalinformation in a header portion of a datagram and associates adetermined position of a sending terminal node with the source address.The server selects services and/or announcements according to theposition associated with the source address.

With another aspect of the invention, a terminal node receives serviceconfiguration information, e.g., an Electronic Service Guide (ESG),about services supported by a communications system in different serviceregions. The terminal node determines services that are supported in anarea defined by the terminal node's geographical position and specifiedradius and correspondingly constructs a service filter.

With another aspect of the invention, header formats for the insertedgeographical information in a propagated signal between a terminal nodeand a serving network are provided. The propagated signal contains atleast one IPv6 datagram that supports the geographical-based service.

With another aspect of the invention, an attachment point insertsgeographical information into a datagram if a terminal node has notincluded the geographical information.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention and theadvantages thereof may be acquired by referring to the followingdescription in consideration of the accompanying drawings, in which likereference numbers indicate like features and wherein:

FIG. 1 shows an architecture of a communications system that supports ageographical-based service in accordance with an embodiment of theinvention;

FIG. 2 shows a flow diagram for a terminal node, as shown in FIG. 1, inaccordance with an embodiment of the invention;

FIG. 3 shows a flow diagram for an access point, as shown in FIG. 1, inaccordance with an embodiment of the invention;

FIG. 4 shows a flow diagram for a content server, as shown in FIG. 1, inaccordance with an embodiment of the invention;

FIG. 5 shows a first layout of a message that supports ageographical-based service in accordance with an embodiment of theinvention;

FIG. 6 shows a second layout of a message that supports ageographical-based service in accordance with an embodiment of theinvention;

FIG. 7 shows an architecture for a terminal node that supports ageographical-based service in accordance with an embodiment of theinvention;

FIG. 8 shows an architecture of a network that supports ageographical-based service in conjunction with a DVB-T network inaccordance with an embodiment of the invention;

FIG. 9 shows a portion of a service area that is supported by the DVB-Tnetwork that is shown in FIG. 8;

FIG. 10 shows serving regions for a terminal node corresponding todifferent geographical-based services and a range set by the terminalnode within the communications system that is shown in FIG. 1;

FIG. 11 represents a service configuration that is associated with anElectronic Service Guide (ESG) of a communications system that supportsgeographical-based services in accordance with an embodiment of theinvention; and

FIG. 12 shows a flow diagram for the terminal node, as shown in FIG. 10,in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

In the following description of the various embodiments, reference ismade to the accompanying drawings which form a part hereof, and in whichis shown by way of illustration various embodiments in which theinvention may be practiced. It is to be understood that otherembodiments may be utilized and structural and functional modificationsmay be made without departing from the scope of the present invention.

FIG. 1 shows an architecture of a communications system 100 thatsupports a geographical-based service in accordance with an embodimentof the invention. As an example, a terminal node 107 establishes a dataconnection to a wireless attachment point 113, which provides access forterminal node 107 to a network 109. Network 109 supportsgeographical-based services for terminal nodes 101–107. (Wirelessattachment point 113 provides access for terminal nodes 105 and 107,while a wireless attachment point 111 provides access for terminal nodes101 and 103.) Wireless attachment point 113 may be implemented in anumber of ways, including a wireless local area network (WLAN) accesspoint, a router, a hub, a bridge, a BlueTooth access point, and a basestation of a wireless system. The base station may support differentwireless standards, including General Packet Radio Service (GPRS) andUniversal Mobile Telecommunications System (UMTS). A terminal node(e.g., terminal nodes 101–107) may correspond to different terminaltypes, including a mobile phone or a computer, such as a laptop orpersonal computer (PC) that may change location or that may bestationary. Also, the terminal node may interact with network through acommunications channel, including a wireless communications channel, adial-up telephone connection, and a cable connection.

In the exemplary embodiment, terminal node 107 comprises a mobile nodethat communicates to network 109 over a wireless communications channel.In the embodiment, terminal node 107 transmits and receives IPv6datagrams that support a geographical-based service, although otherembodiments of the invention may support datagrams with another format.The IPv6 datagrams are compatible with RFC 2460 (e.g., InternetProtocol, Version 6, December 1998). Moreover, the embodimentadditionally utilizes an extension header to provide geographicalinformation in the datagram. The geographical information includes ageographical position that is associated with terminal node 107. Forexample the geographical position may comprise the approximate locationof terminal node 107. The geographical information may include otherinformation such as a velocity of terminal node 107. The geographicalinformation is explained in greater detail in the context of FIGS. 5 and6. In the following discussion, a geographical extension header thatcontains geographical position data, e.g., as latitude, longitude, andaltitude, is referred as a GPIPv6 header.

In the embodiment, datagrams from terminal node 107 are routed fromwireless attachment point 113 through a router 119 to a content server115. From the geographical position of terminal node 107, content server115 determines what services can be supported for terminal node 107. Forexample, communications system 100 may be configured to supportdifferent services in different serving areas. In the exemplaryembodiment shown in FIG. 1, terminal nodes 105 and 107 are approximatelylocated at geographical position 1 and terminals 101 and 103 areapproximately located at geographical position 2. (In the embodiment,the geographical position is provided by the terminal node. However, inother embodiments, the geographical position may be inserted by anentity of the serving network, e.g., attachment point 113.) Contentserver 115 parses the geographical position and associates acorresponding IPv6 source address with the geographical position. Inaddition, content server 115 associates services and/or announcementswith the IPv6 address of terminal node 107. Table 1 illustrates anexemplary mapping of the IPv6 addresses of terminal nodes 101–107 to thecorresponding geographical positions, services and announcements.

TABLE 1 Service Configuration Geographical IPv6 address positionServices Announcements 1 1 Service set 1 Set 1 2 1 Service set 1 Set 1 32 Service set 2 Set 2 4 2 Service set 2 Set 2

FIG. 2 shows a flow diagram 200 for a terminal node (e.g., terminal node107), as shown in FIG. 1, in accordance with an embodiment of theinvention. Step 201 starts process 200. In step 203, terminal node 107establishes a connection to attachment point 113. In step 205, adatagram that contains the geographical position of terminal node 107 istransmitted from terminal node 107 requesting for services andannouncements from content server 115.

FIG. 3 shows a flow diagram 300 for an access point (e.g., wirelessattachment point 113), as shown in FIG. 1, in accordance with anembodiment of the invention. Step 301 starts process 300. In step 303,the access point waits for a datagram from terminal node 107. If adatagram is received from terminal node 107, as determined by step 305,wireless attachment point 113 determines if a geographical position hasbeen inserted by terminal node 107. If not, wireless attachment point113 inserts a geographical position that corresponds to the location ofwireless attachment point 113 in step 307. In step 309, the datagram isforwarded to the content server, as designated in the destinationaddress of the datagram, through router 119. Process 300 is repeated forthe next received datagram in step 311.

FIG. 4 shows a flow diagram for a content server (e.g., content server115), as shown in FIG. 1, in accordance with an embodiment of theinvention. Step 401 starts process 400. In step 403, content server 115waits for a datagram with a GPIPv6 header. If a datagram is received, asdetermined by step 405, content server 115 parses the geographicalposition data and associates the determined position with the IPv6source address (that is contained in the IP datagram), which correspondsto terminal node 107 in step 407. In step 409, content server 115associates available services and announcements that are available toterminal node 107 for the geographical position of terminal node 107 (asillustrated in Table 1).

FIG. 5 shows a layout of a message 500 that supports ageographical-based service in accordance with an embodiment of theinvention. Datagram 500 comprises header information 501 (such as thesource IP address and the destination address) and data payload 537.Also, datagram 500 comprises geographical position information about asource device corresponding to a option type data field 540, an optionlength data field 541, a reserved data field 549, a version data field551, a datum data field 553, a latitude data field 503, a longitude datafield 505, an altitude data fields 507 and 539, velocity data fields509, 511, 513, and 515, location uncertainty data fields 517, 519, 521,523, and 525, velocity uncertainty data fields 527, 529, 531, and 533,and time data field 535.

Time data field 535 is a 40-bit field that contains the current time anddata in Coordinated Universal Time (UTC) and Modified Julian Date (MJD).Field 535 is coded as 16 bits providing 16 LSBs of the MJD followed by24 bits that represent 6 digits in a 4-bit Binary-Coded Decimal (BCD).In the exemplary embodiment, the geographical information is containedin a destination options header or in a hop-by-hop header, in compliancewith RFC 2460. In the embodiment, a destination options header and ahop-by-hop header may be contained in the same datagram.

Referring to FIG. 5, the full width corresponds to 32 bits (4 octets).However, other embodiments of the invention may utilize different datafield alignments and different data widths for any of the data fields.In the exemplary embodiment, the data fields may be contained in aheader that is compatible with RFC 2460.

In the exemplary embodiment, version data field 551 is a 8-bit fieldthat indicates the version of the message header. Datum data field 553is a 8-bit field that indicates the used map datum (e.g., standardMIL-STD-2401) for determining the geographical position. Latitude datafield 503 is a 32-bit field that indicates the latitude value of thesource device (e.g., corresponding to an approximate location ofterminal node 107) presented in ANSI/IEEE Std 754-1985 format. Longitudedata field 505 is a 32-bit field that indicates the longitude value ofthe source device presented in ANSI/IEEE Std 754-1985 format. Altindicator data field 539 is a 1-bit field indicating the use of altitudeinformation. Altitude data field is a 16-bit field that indicates thealtitude value of the source device presented in ANSI/IEEE Std 754-1985format.

Velocity indicator data field 509 is a 1-bit field indicating the use ofvelocity information. If velocity information is included, this field isset to ‘1’. Otherwise this field is set to ‘0’. Heading data field 511is a 16-bit field that indicates the direction where the mobile node ismoving. If velocity indicator data field 509 is set to ‘0’, this fieldis ignored. Otherwise, this field is included and is set to the angle ofaxis of horizontal velocity uncertainty, in units of 5.625 degrees, inthe range from 0 to 84,375 degrees, where 0 degrees is True North andthe angle increases toward the East. Vertical velocity data field 513 isan 8-bit field, which indicates the vertical velocity of the mobilenode. Vertical velocity data field 513 is used if field 509 is set to‘1’. Horizontal velocity data field 515 is a 16-bit field that indicatesthe horizontal velocity of the mobile node. If velocity indicator is setto ‘1’, this field is in use. Once used, the horizontal speed is set inunits of 0.25 m/s, in the range from 0 to 511.75 m/s. Otherwise thisfield is ignored.

Loc_Unc_H indicator data field 517 is a 1-bit field which indicates thehorizontal position uncertainty, including elliptical. If ellipticalhorizontal position uncertainty information is included in this responseelement, this field is set to ‘1’. Otherwise, this field is set to ‘0’.Loc_Unc angle data field 519 (angle of axis of the standard errorellipse for horizontal position uncertainty) is a 8-bit field indicatingthe angle of axis of the standard error ellipse for horizontal positionuncertainty. If Loc_Unc_H indicator field 517 is set to ‘0’, this fieldis ignored. Otherwise, this field is included and is set to angle ofaxis for horizontal position uncertainty, in units of 5.625 degrees, inthe range from 0 to 84.375 degrees, where 0 degrees is True North andthe angle increases toward the East. Loc_Unc A data field 521 (standarddeviation of error along angle specified for horizontal positionuncertainty) is a 8-bit field indicating the Standard deviation of erroralong angle specified for horizontal position uncertainty. If Loc_Unc Adata field 521 is set to ‘0’, this field is ignored. Otherwise, thisfield is included and is set to represent the standard deviation of thehorizontal position error along the axis corresponding to Loc_Unc angledata field 519. Loc_Unc P data field 523 (standard deviation of erroralong angle specified for horizontal position uncertainty) is a 8-bitfield indicating standard deviation of error along angle specified forhorizontal position uncertainty. If Loc_Unc P data field 523 is set to‘0’, this field is ignored. Otherwise, this field is included and is setto represent the standard deviation of the horizontal position errorperpendicular to the axis corresponding to Loc_Unc angle data field 519.Loc_Unc vertical data field 525 (standard deviation of vertical errorfor position uncertainty) is a 8-bit field indicating standard deviationof vertical error for position uncertainty.

Vel_Unc angle data field 527 (angle of axis of standard error ellipsefor horizontal velocity uncertainty) is a 8-bit field indicating theangle of axis of standard error ellipse for horizontal velocityuncertainty. If Vel_Unc angle data field 527 is set to ‘0’, this fieldis ignored. Otherwise, this field is set to the angle of axis forhorizontal velocity uncertainty, in units of 5.625 degrees, in the rangefrom 0 to 84,375 degrees, where 0 degrees is True North and the angleincreases toward the East. Vel_Unc A data field 529 (standard deviationof error along angle specified for horizontal velocity uncertainty is a8-bit field indicating standard deviation of error along angle specifiedfor horizontal velocity uncertainty. If velocity indicator data field509 is set to ‘1’, this field is included and is set to represent thestandard deviation of the horizontal velocity error along the anglecorresponding to Vel_Unc angle data field 527. Vel_Unc P data field datafield 531 (standard deviation of error perpendicular to angle specifiedfor horizontal velocity uncertainty) is a 8-bit field indicatingstandard deviation of error perpendicular to angle specified forhorizontal velocity uncertainty. If velocity indicator data field 509 isset to ‘1’, this field is included and is set to represent the standarddeviation of the horizontal velocity error perpendicular to the anglecorresponding to Vel_Unc angle data field 527. Otherwise, this field isignored. Vel_Unc vertical data field 533 (standard deviation of verticalvelocity error) is an 8-bit field indicating the standard deviation ofvertical velocity error.

In the embodiment, location uncertainty data fields 519–525 may be usedto define a geographical area, where the data of location uncertaintydata fields may not be as specified by Standards, but can be used by anapplication for conveying region information. In such a case, theapplication could recognize the use of location uncertainty data fields519–525 and/or the variation from the specification as indicated in someother field of the header.

FIG. 6 shows a second layout of a message 600 that supports ageographical-based service in accordance with an embodiment of theinvention. Datagram 600 comprises header information 601 (such as thesource IP address and the destination address) and data payload 637.Also, datagram 600 comprises geographical position information about adestination position corresponding to a option type data field 640, anoption length data field 641, a reserved data field 657, a version datafield 651, a datum data field 653, a latitude data field 603, alongitude data field 605, an altitude data field 607, and radius fields609 and 655. In the exemplary embodiment, the geographical informationis contained in a destination options header or in a hop-by-hop header,in compliance with RFC 2460.

Referring to FIG. 6, the full width corresponds to 32 bits (4 octets).However, other embodiments of the invention may utilize different datafield alignments and different data widths for any of the data fields.In the exemplary embodiment, the data fields may be contained in aheader that is compatible with RFC 2460.

In the exemplary embodiment, version data field 651 is an 8-bit fieldthat indicates the version of the message header. Datum data field 653is a 8-bit field that indicates the used map datum (e.g., standardMIL-STD-2401) for determining the geographical position. Latitude datafield 503 is a 32-bit field that indicates the latitude value of thedestination position presented in ANSI/IEEE Std 754-1985 format.Longitude data field 505 is a 32-bit field that indicates the longitudevalue of the destination position presented in ANSI/IEEE Std 754-1985format. Alt indicator data field 639 is a 1-bit field indicating the useof altitude information. Altitude data field is a 16-bit field thatindicates the altitude value of the destination position presented inANSI/IEEE Std 754-1985 format. Radius data field 609 is a 16-bit fieldthat indicates the horizontal radius in meters from the destinationposition. Radius indicator data field is a 1-bit field that indicatingthe use of the radius information that is contained in radius data field609. If set to ‘1’, radius data field 609 is present.

With the embodiment, a separate message is not required to providegeographical information. An IPv6 datagram, shown in FIGS. 5 and 6, maycarry both geographical information as well as a payload that isassociated with a geographical-based feature. Combining these functionsinto the same datagram may facilitate processing the datagrams by aserver that supports the geographical-based service. In a variation ofthe invention, header information in message 600 (corresponding todestination position) may be included in the same message as message 500(corresponding to source position) in the same datagram. The headerinformation may be supported in a IPv6 destination options header or ina IPv6 hop-by-hop header.

FIG. 7 shows an architecture for a terminal node 700 that supports ageographical-based service in accordance with an embodiment of theinvention. Terminal 700 comprises a processor 701, a communicationsmodule 703, a memory 705, a user interface 707, and a locationdetermination module 709. Processor 701 executes computer instructionsthat are retrieved from memory 705. Also, processor 701 retrieves andsaves data from/to memory 705.

Terminal node 700 (that may correspond to terminal node 107 as shown inFIG. 1) communicates with access point 113 (as shown in FIG. 1) throughcommunications module 703. In the exemplary embodiment, communicationsmodule supports a wireless communications channel and transmits throughan antenna 711. However, other embodiments of the invention may supportother communications channels such as a dial-up telephone connectionthat do not necessitate antenna 711.

In the embodiment, terminal node 700 obtains geographical positioninformation through location determination module 709. Locationdetermination module comprises a Global Position Satellite (GPS)receiver in order to derive position information. Location determinationmodule 709 receives radio signals through antenna 713 from a pluralityof GPS satellites. From the gathered information, location determinationmodule 709 derives an approximate position of terminal node 700.

Other embodiments of the invention may utilize other methods fordetermining a geographical position of terminal node 700, includingassisted GPS, cell identification (corresponding to the location of thecell that terminal node is located), and time difference of arrival(TDOA). In some embodiments, antenna 713 may not be implemented becauseantenna may not be required to determine the geographical position ofterminal node 700.

A user may provide commands and data to terminal node 700 through userinterface 707. For example, the user may input an approximate set ofposition coordinates (e.g., latitude and longitude) rather than havinglocation determination module 709 deriving the geographical position ofterminal node 700. Also, if terminal node 700 receives a datagram fromanother terminal node, in which the datagram contains anothergeographical position of the other terminal node, the other geographicalposition may be displayed on user interface 707.

FIG. 8 shows a network architecture 800 that supports ageographical-based service in conjunction with a Digital VideoBroadcasting-Terrestrial (DVB-T) network 805 in accordance with anembodiment of the invention. A terminal node 801 is connected to aninteraction network 803 (which may be supported by network 109 as shownin FIG. 1) through a wireless communications channel. To illustrateservices that can be supported by network 800, a user (e.g., arestaurant) of terminal node 801 wishes to send a video message to otherterminal nodes in the vicinity the restaurant in order to broadcast aspecial meal of the day. The broadcasting of the advertisement issupported by DVB-T network 805. DVB-T network 805 typically hasunidirectional transmission capabilities to terminal nodes and typicallyis capable of supporting multicast services with massive data bandwidthfor the downlink communications channel. DVB-T network 805 may not havean appreciable capacity of directly receiving messages from terminalnodes (corresponding to the uplink communications channel).

In the architecture shown in FIG. 8, terminal node 801 requests for theadvertisement to be broadcast by DVB-T network 805 through interactionnetwork 803. Terminal node 801 initiates the request by sending datagram851, which includes a GPIPv6 header and other data, to interactionnetwork 803. In the embodiment, interaction network 803 supports aninteraction network protocol in order to interact with DVB-T network805. Terminal node 801 specifies a region 807 over which theadvertisement is to be broadcast. In the example shown in FIG. 8,terminal nodes 809–813 are within region 807 and thus terminal nodes809–813 receive the advertisement when the advertisement is broadcast.Region 807, which is an approximate circle, is determined by a specifiedradius and a destination position that correspond to the approximateradius and center, respectively. (The destination position maycorrespond to the geographical position of terminal node 801 or may be aset of coordinates that is different from the geographical position ofterminal node 801.) In order to specify the destination coordinates andthe radius, terminal node 801 may send an IPv6 datagram that includesheader information and a data payload (corresponding to theadvertisement) as shown in FIG. 6.

FIG. 9 shows a portion of a service area 900 that is supported by theDVB-T network 805 that is shown in FIG. 8. Service area 900 is supportedby cells 901–907. Region 807, as specified by terminal node 801, iscontained entirely with cell 903. Thus, DVB-T network 805 broadcasts anadvertisement from terminal node 801 over cell 903. Also, the embodimentsupports a scenario in which a requested region spans a plurality ofcells.

For example a requested region 951 spans cells 901–905. If terminal node801 were to specify region 951 rather than region 807, the advertisementwould be broadcast over cells 901–905.

FIG. 10 shows serving regions for different geographical-based servicesthat communications system 100 can support a terminal node 1001 for therange set by terminal node 1001. In the example shown in FIG. 10, system100 is configured to support different services in different regions. Aservice 1 is supported in region 1005; a service 2 is supported inregion 1007; and a service 3 is supported in region 1009. System 100 maynotify terminal node 1001 about the service configuration by sending anannouncement that provides an Electronic Service Guide (ESG). (The ESGis discussed in more detail with FIG. 11.) Terminal node 1001 isconfigured to receive broadcasts over an approximate circular region1003, in which the center corresponds to the position of terminal node1001 and the radius is specified by the user of terminal node 1001through a user interface (e.g., user interface 707 as shown in FIG. 7).In the exemplary embodiment, as shown in FIG. 10, terminal node 1001 isable to receiver services 1 and 3.

FIG. 11 represents a service configuration 1100 that is associated witha service guide (e.g., Electronic Service Guide (ESG)) of communicationssystem 100 for supporting geographical-based services in accordance withan embodiment of the invention. Service configuration 1100 correspondsto the service configuration that is shown in FIG. 10. Eachgeographical-based service is supported over an approximate circularregion that is specified by center coordinates 1103 and radius 1105.Service 1107 (service 1) has center coordinates 1113 and radius 1115.Service 1109 (service 2) has center coordinates 1117 and radius 1119.Service 1111 (service 3) has center coordinates 1121 and radius 1123.Terminal node 1001 is located at center coordinates 1127 and specifiesradius 1129 for services. With the corresponding geometry, terminal node1001 determines what services are available at its current location. Ofcourse, if terminal node 1001 changes locations, a different set ofservices may be available and thus are recalculated.

FIG. 12 shows a flow diagram 1200 for the terminal node 1001 fordetermining available services in accordance with an embodiment of theinvention. If a service is available and if the user wishes to utilizethe service, the service is configured in a filter. The filter processesdatagrams that are associated with the selected services. In step 1101,terminal node 1001 determines its position coordinates, utilizinglocation determination module 709 (as shown in FIG. 7). In step 1103,terminal node 1001 sets criteria for determining available services byutilizing center coordinates 1127 and radius 1129. In step 1205, usingthe service configuration broadcast by system 1000 in an announcement,terminal node 1101 selects services that match coordinate and radiuscriteria. In the example shown in FIG. 10, terminal node 1001correspondingly selects service 1107 (service 1) and service 1111(service 3). In step 1207, terminal 1001 configures a message filter, inwhich datagrams corresponding to service 1107 and service 1111 areprocessed.

As can be appreciated by one skilled in the art, a computer system withan associated computer-readable medium containing instructions forcontrolling the computer system can be utilized to implement theexemplary embodiments that are disclosed herein. The computer system mayinclude at least one computer such as a microprocessor, digital signalprocessor, and associated peripheral electronic circuitry.

While the invention has been described with respect to specific examplesincluding presently preferred modes of carrying out the invention, thoseskilled in the art will appreciate that there are numerous variationsand permutations of the above described systems and techniques that fallwithin the spirit and scope of the invention as set forth in theappended claims.

1. A method for supporting a geographical-based service for at least oneterminal node in a communications system, the method comprising: (a)determining a first geographical position that is associated with afirst terminal node; (b) inserting the first geographical position and aspecified radius into a message header of a first datagram, thespecified radius being indicative of a serving area for thegeographical-based service; (c) sending, by the first terminal node, thefirst datagram; (d) receiving, by another terminal node, the firstdatagram; (e) determining another geographical position, the othergeographical position being associated with the other terminal node; and(f) if the other terminal node is within an approximate circular area,accepting the first datagram, wherein the approximate circular area isspecified by the specified radius in relation to the first geographicalposition.
 2. The method of claim 1, wherein the first geographicalposition is indicative of an approximate location of the first terminalnode.
 3. The method of claim 1, wherein the first geographical positionin indicative of an approximate destination position.
 4. The method ofclaim 1, wherein (a) comprises: (i) acquiring the geographical positionby the terminal node with a Global Position Satellite (GPS) locationdetermination module.
 5. The method of claim 1, wherein (a) comprises:(i) obtaining the first geographical position from a serving network. 6.The method of claim 1, wherein (a) comprises: (i) obtaining the firstgeographical position through a user interface.
 7. The method of claim1, wherein (a) comprises: (i) acquiring the geographical position byutilizing a time difference of arrival (TDOA) technique.
 8. The methodof claim 1, wherein (b) comprises: (i) selecting a selected datagram;and (ii) inserting the geographical position into a message header ofthe selected datagram.
 9. The method of claim 1, further comprising: (g)inserting an indicator into the first datagram, wherein the indicatorrestricts processing of the first geographical position by anotherentity of the communications system.
 10. The method of claim 1, whereinthe datagram complies with an Internet Protocol version 6 (IPv6)specification and wherein (b) comprises inserting the first geographicallocation into an extension header of the first datagram.
 11. The methodof claim 10, wherein the extension header comprises a destination optionheader.
 12. The method of claim 10, wherein the extension headercomprises a hop-by-hop header.
 13. The method of claim 1, wherein thecommunications system comprises a wireless system and the first terminalnode comprises a mobile node.
 14. The method of claim 1, wherein thefirst terminal node is selected from the group consisting of a wirelesstelephone, a workstation, a personal computer (PC), and a stationarycommunications device.
 15. The method of claim 1, wherein (a) comprises:(i) selecting a technique for determining the first geographicalposition.
 16. The method of claim 15, further comprising: (g) insertinga technique identification into the message header of the firstdatagram, the technique identification identifying the selectedtechnique for determining the first geographical position.
 17. Themethod of claim 1, wherein the first geographical position comprises anapproximate longitude and an approximate latitude of a position of theterminal node.
 18. The method of claim 1, further comprising: (g)displaying, by the other terminal node, information that is indicativeof the first geographical position.
 19. The method of claim 1, whereinthe first datagram is contained in a stream of datagrams.
 20. The methodof claim 1, further comprising: (g) inserting an indicator into thefirst datagram, wherein the indicator restricts processing of the firstgeographical position and a destination location by another entity ofthe communications system.
 21. A computer-readable medium havingcomputer-executable instructions for supporting a geographical-basedservice for at least one terminal node in a communications systemperforming the steps of: (a) determining a first geographical positionthat is associated with a first terminal node; (b) inserting the firstgeographical position and a specified radius into a message header of afirst datagram, the specified radius being indicative of a serving areafor the geographical-based service; (c) sending, by the first terminalnode, the first datagram; (d) receiving, by another terminal node, thefirst datagram; (e) determining another geographical position, the othergeographical position being associated with the other terminal node; and(f) if the other terminal node is within an approximate circular area,accepting the first datagram, wherein the approximate circular area isspecified by the specified radius in relation to the first geographicalposition.
 22. The computer-readable medium of claim 21, further havinginstructions for performing the step of: (g) inserting an indicator intothe first datagram, wherein the indicator restricts processing of thefirst geographical position by another entity of the communicationssystem.
 23. A method for supporting at least one geographical-basedservice, the method comprising: (a) determining a geographical positionthat is indicative of an approximate location of a mobile node; (b)determining a specified radius, the specified radius being a maximumdistance from the geographical position; (c) receiving an announcement,the announcement containing an identification of a service, a servicegeographical position, and a service radius, the service geographicalposition and the service radius being associated with a network entitysupporting the service; (d) determining whether a service areacorresponding to the service geographical position and the serviceradius is within a circular area, the circular area being determined bythe geographical position and the specified radius; (e) if the servicearea is within the circular area, including the identification of theservice in a filter to designate that the service is acceptable; (f)receiving a datagram that supports the service; (g) if the service isacceptable, accepting the datagram; and (h) if the service is notacceptable, rejecting the datagram.
 24. The method of claim 23, furthercomprising: (i) detecting that the mobile node has moved to anothergeographical position; (j) in response to (i), determining if theservice is acceptable; and (k) modifying the filter in accordance with(j). 2 .
 25. The method of claim 23, wherein (a) comprises: (i)acquiring the geographical position by the terminal node with a GlobalPosition Satellite (GPS) location determination module.
 26. The methodof claim 23, wherein (a) comprises: (i) obtaining the geographicalposition from a serving network.
 27. The method of claim 23, wherein (a)comprises: (i) obtaining the geographical position through a userinterface.
 28. The method of claim 23, wherein (a) comprises: (i)acquiring the geographical position by utilizing a time difference ofarrival (TDOA) technique.
 29. The method of claim 23, wherein (a)comprises: (i) selecting a technique for determining the geographicalposition.
 30. The method of claim 23, wherein the geographical positioncomprises an approximate longitude and an approximate latitude of aposition of the mobile node.